Browsing Institute's contributions by Subject "denitrification"
Now showing items 1-20 of 39
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A preliminary study of anaerobic thiosulfate-oxidising bacteria as denitrifiers in the Arabian Sea
(Taylor & Francis, 1988)Bacteria which oxidize thiosulfate and reduce nitrate (TONRB) and bacteria which oxidize thiosulfate and denitrify (TODB) sampled at 5-, 100-, 200-and 300-m depths were enumerated in agar shake cultures by colony counting ... -
Activity of the respiratory electron transport system and respiration rates within the oxygen minimum layer of the Arabian Sea
(Pergamon, 1993)Measurements of the activity of the respirtory electron transport system (ETS) at 15 stations in the Arabian Sea during the northeast monsoon (December 1988) yield high respiration rates that do not correlate with the ... -
An evaluation of physical and biogeochemical processes regulating the oxygen minimum zone in the water column of the Bay of Bengal
(American Geophysical Union, 2002)Monthly oxygen budgets for the intermediate waters (100-1000 m) of the Bay of Bengal were constructed based on Modular Ocean Model (MOM) and oxygen data. The model results reveal that the oxygen levels in the oxygen minimum ... -
An intermediate nepheloid layer associated with high microbial metabolic rates and denitrification in the northwest Indian Ocean
(American Geophysical Union, 1993)Extensive optical, physical chemical, and biochemical measurements made simultaneously in the northwest Indian Ocean reveal the occurrence of an intermediate nepheloid layer (INL) invariably associated with the secondary ... -
Anaerobic nitrification–denitrification mediated by Mn-oxides in meso-tidal sediments: Implications for N2 and N2O production..
(Elsevier, 2015)Field measurements in the Arcachon Bay (southwest France) indicated anaerobic production of NOx via nitrification, which was coupled to the reduction of Mn-oxides. To prove the occurrence of this process, laboratory microcosm ... -
Carbon dioxide and nitrous oxide in the Arabian Sea
(American Geophysical Union, 1993)This review concentrates on some aspects of biogeochemical cycling of carbon and nitrogen in the Arabian Sea with emphasis on the atmospheric fluxes of CO sub(2) and N sub(2)O. The Arabian Sea appears to serve as a net ... -
Chemical Oceanography of the Arabian sea. Part - V. Hydrochemical Characteristics off the Central West Coast of India
(CSIR-NISCAIR, 1980)Data from Arabian Sea cruises 46 (December 1978) and 59 (October 1979) of R V Gaveshani have been used to calculate rates of denitrification at intermediate depths (72-1200 m). About 34% of the available nitrate-nitrogen ... -
Chemical oceanography of the Indian Ocean, North of the equator
(Elsevier, 1984)Chemical oceanographic studies in the North Indian Ocean have revealed several interesting and unique features. Dissolved oxygen northern boundary, prevents quick renewal of subsurface reducing conditions prevail at ... -
Denitrification exceeds anammox as a nitrogen loss pathway in the Arabian Sea oxygen minimum zone
(Elsevier, 2010)The oxygen minimum zones (OMZs) of the world oceans are sites of enhanced anaerobic nitrogen transformations, such that the largest OMZ, the Arabian Sea, is responsible for 30-50% of the oceanic water column fixed N loss. ... -
Denitrification in the Arabian Sea
(Elsevier, 1982)Estimates of the amount of denitrification in the Arabian Sea are inconsistent, and so two methods of calculations of 'original' nitrate concentrations used in earlier studies have been reviewed. Nitrite at intermediate ... -
Denitrification prevails over anammox in tropical mangrove sediments (Goa, India)
(Elsevier, 2012)Denitrification, anammox (Anx) and di-nitrogen fixation were examined in two mangrove ecosystems- the anthropogenically influenced Divar and the relatively pristine Tuvem. Stratified sampling at 2 cm increments from 0 to ... -
Denitrification processes in the Arabian Sea
(Indian Academy of Sciences, Bangalore, 1994)Recent information on some consequences of the acute mid-water oxygen deficiency in the Arabian Sea, especially on carbon-nitrogen cycling, is reviewed. An evaluation of published estimates of water column denitrification ... -
Denitrification rates and excess nitrogen gas concentrations in the Arabian Sea oxygen deficient zone
(Elsevier, 2006)Rates of canonical, i.e. heterotrophic, water-column denitrification were measured by sup(15)N incubation techniques at a number of coastal and open ocean stations in the Arabian Sea. Measurements of N2 :Ar gas ratios were ... -
Denitrifying bacterial community composition changes associated with stages of denitrification in oxygen minimum zones
(Springer, 2009)Denitrification in the ocean is a major sink for fixed nitrogen in the global N budget, but the process is geographically restricted to a few oceanic regions, including three oceanic oxygen minimum zones (OMZ) and hemipelagic ... -
Diversity of nitrite reductase genes (nirS) in the denitrifying water column of the coastal Arabian Sea
(Inter-Research, 2004)Denitrification often occurs in the water column, underlying zones of intense productivity and decomposition in upwelling regions. In the denitrifying zone off the southwest coast of India, high concentrations of nitrite ... -
Formation of anoxia and denitrification in the bottom waters of a tropical estuary, southwest coast of India.
(Copernicus Publications, 2010)Hydrographic characteristics of the southwest coast of India and its adjoining Cochin backwaters (CBW) were studied during the summer monsoon. Anomalous formation of anoxia and denitrification were observed in the bottom ... -
Hydrochemistry of the Bay of Bengal: Possible reasons for a different water-column cycling of carbon and nitrogen from the Arabian Sea
(Elsevier, 1994)A study on biogeochemical cycling in the western Bay of Bengal was undertaken during two seasons (pre-southwest monsoon and northeast monsoon of 1991). Relationships of the conservative tracers NO and PO with potential ... -
Increased marine production of N sub(2)O due to intensifying anoxia on the Indian continental shelf
(Macmillan, 2000)Eutrophication of surface waters and hypoxia in bottom waters has been increasing in many coastal areas, leading to very large depletions of marine life in the affected regions. These areas of high surface productivity and ... -
Is delta sup(15)N of sedimentary organic matter a good proxy for paleodenitrification in coastal waters of the eastern Arabian Sea?
(American Geophysical Union, 2009)Recently published sedimentary records of delta sup(15)N from several coastal areas affected by both natural and anthropogenically produced shallow hypoxia with the objective of testing this as a proxy for denitrification ... -
Isotopic composition of nitrate in the central Arabian Sea and eastern tropical North Pacific: A tracer for mixing and nitrogen cycles
(American Society of Limnology and Oceanography, 1998)The delta sup(15)N composition of nitrate and N sub(2) gas was measured in the eastern tropical North Pacific (ETNP) and central Arabian Sea (AS) suboxic regions. The delta sup(15)N of nitrate increased from 6 ppt at 2,500 ...